Sealing material



June 15 1926.

H. M. E. HEINICKE `SEALING MATERIALy Filed April 28, 1924 f m @y Patented June 15, 1926.

UNITED srarss PATENT orifice.v

HERBERT MARTIN EDWARD IIEINICKE, 0F ELGTN, ILLINOS, ASSIGNOR T0 WEST- ERN ELECTRIC COMPANY, INCORPORATED, OF NEW' YORK, N. Y., A CORPORATION 0F NEW YORK.

SEALING MATERIAL.

Application mea April as,

This invention relates to an improved sealing material for sealing annealing containers and a method of applying the same.

In the practice of heat treating metals one method employed is to provide receptacles in which to place the parts to be treated, the purpose being to prevent as much as possible oxidation of the part-s during the application of heat. These receptacles, generally termed annealing boxes or pots, are provided with covers, the boX and cover being so formed that sealing material can be placed around the jointure so as to prevent circulation of air into the annealing boX.

One material which has been used generally for the purpose of sealing containers of this type is fire-clay. This material, however, contains impurities which when certain types of material. are treated, may have an injurious effect upon the material. In addition, the lire-clay and other materials of like nature when heated usually become somewhat porous and developl small cracks and apertures. These apertures are undesirable because when the box containing the material is cooled, air is sucked into the interior of the box through these apertures and the treated parts adjacent to the point of in# take of air become oxidized. l.

One object of this invention is to provide .a material for sealing annealing containers which is free from ingredients which-will deleteriously affect the metal annealed.

Another object of the invention is to provide a method for sealing receptacles for containing materials to be heated which will allow egress of vapors from the receptacle but will not allow a flow of air into the receptacle.

A further object of this invention is to provide a method for sealing a receptacle for containing materials to be heated which will cause a partial vacuum to be formed within the receptacle.

The invention consists in the employment of a plurality of materials as a seal, one of the materials employed being refractory and self-retaining and another material being of such anature that it will fuse at a compara- 1924. serial No. 769,708.

tiveiy low temperature and lill up the interstices of the refractory, self-retaining mate# rial. y

ln the accompanying drawing:

Fig. 1 is a cross-section of an annealing pot in which the invention isshown embodied.

Fig. 2 isa plan view of the annealing pot with the cover partly out away.

Fig. 3 is an enlarged fragmentary view showing part of the structure of Fig. 1.

Referring to the accompanying drawing showing one embodiment of the invention, 10 is an annealing pot having a flanged rim 11 forming a grooved portion 12. A cover 13 has a flange 14 adapted to extend into the groove 12 when the cover is placed on the pot. lit-hin the grooved portion 12 is refractory, self-retaining material 15 and sprinkled on the refractory, self-retaining material is a material 16 which will fluir at a comparatively low temperature. The sealing material can be applied in any suitable manner, but it is preferable to apply it as follows:

First, the materials which are to be treated are placed within the container; then the groove 12 of the container is filled with a refractory, self-retaining material, and the Hang@ 14: of the cover 13 forced down into this material asindieated in Figs. 1 and 3. Additional refractory, self-retaining materialv is forced around the cover 13 and into the groove 12, and on top of the refractory, self-retaining material is then. placed the material 16 whichwill fluxat a comparatively low temperature.V

The refractory, self-retaining material referred to above can be any refractory clay, such as the lire clays usually employed as sealing material. Fire-clay, however, contains sulphur and other impurities and it is therefore not a good material to use-for some classes of work.' For instance, in the annealing of nickel iron alloys, a small amount of sulphur will cause appreciable brittleness of the annealed parts. Ordinary loam may therefore be used in place of fire-clay where this class of material is treated. It is also desirable to u se ordinary loam in other classes of Work because it is in general considerably cheaper in price than most socalled refractory clays.

A suitable material that can bc used for the purpose of sealing the cracks and pores in the self-retaining material is ordinary soda ash or sodium carbonate. Borax may also be used or any stable salt which Will fuse at a con'iparatively low temperature. Loam and soda. ash can be employed very efficiently together because wherever a` wack in the loam appears the soda ash Will iow down into this crack and cause a tluxing ot the loam in such a way as to seal it together.

Another desirable iteature about these two materials in combination is that the soda ash remains sufficiently fluent to allenv vapors to escape through the loam, but as soon as the container begins to cool and the ioiv ot' vapor is in the opposite direction, that is to say the air has a tendency to reenter the pot as the pot cools, the soda ash Will then seal up all the apertures and pores in the loam. This causes a species of vacuumY Within the container which is particularly valuable because the material being treated is thereby protected Ytrom oxidizing intluences until it is below the tempera ture at Which rapid oxidation occurs.

It desirable,4other iluxing materials may be employed in vaddition to the soda ash. A layer ot lalte sand on top otthe soda ash may be used in certain cases to. term a glaze on top of the seal. This is an added precaution, but is not necessary as in the majority of cases the use ot loam and soda ash is sufficient.

It is to be understood that the invention is not confined to the use ot' loam and soda ash, but is only to be limited by the scope of the appended claims.

`What is claimed is l. A method for sealing containers which consists in lilling apertures in the container with a material which is refractory and self-retaining, and then placing'- thereon another material Which is ot such a nature as to till the pores iu the self-retaining' material during heating.

2. A method for sealing the joint between the body portion and cover of an annealing container which consists in placingrefractory, self-retaining material around the body portion et the container in the place Where the cover is seated, placing the cover on the body portion ot' the container and in contact with said refractory material, and then placing in contact with the cover and on top of said refractory material another material which will linx at a comparatively low temperature.

3. A method tor sealing the joint bctween the body portion and cover ot an annealing container which consists in placing loam around the body portion ot the con tainer in the place Where the cover is seated, placing` the cover on the body portion ot the container and in contact with said loam and then placing soda ash in contact with the cover and on top of said loam;

t. A method for sealing the joint between the body portion and cover of an annealing` container which consists in placing loam around the body portion ol the container in the place Where the cover is seated, irilacing the cover on the body portion oif the container and in contact .vtl said loam, placing soda ash in contact With the cover and on top ot said loam., and then placing sand on top ot said soda ash..

5. A method for sealing the jointure bctween the cover and body of an annealing container which consists in sealing sai-l jointure with loam and covering said loam with soda ash.

6. A method for sealing` the jointure between. the cover and body ot an annealing container which consists in sealing said `jointure with loam, cor/erin?` said loam with alayer of soda ash and then covering said soda ash with a layer of sand.

7. A seal for annealing boxes including' a plurality of materials, one of said inaterials being refractory and self-retaining and another of said materials being oi such a nature as to tlux at a comparatively lou' temperature.

8. A seal for annealing containers iucluding loam as an ingredient.

9. A sealing material Ytor annealing containers including a refractory, seit-retaining material and soda ash.

10. A sealing material ior annealing con` tainers including loam and a material which Will lluX at a comparatively loiv temperature.

1l. A sealing material tor annealing' containers including loam and soda ash.

l2. A sealing material tor an annealing container including loam, soda ash and sand. v

ln Witness whereof, l hereunto subscribe my name this 15th day of April A. D.. 1924.

HERBERT MARTIN EDWARD HElNlCKE. 

